Machine for forming spiral tubing.



A. MQMURTRIE.- MACHINE PoR romania SPIBAL TUBING.

v APPLwATIox rum) 011121.11110. 1 1 1 7,686. f Patented Nov,.17, 1914 h,'p1/5 fg Figa. y

UNITED sTATEs PATENT oEEicE,

Annan M'cMURTEIE. or NEW YORK, N. Y.. A-ssIGNon To THOMAS & BETTsCOMPANY, or NEW YORK, N. Y., A CORPORATION OF NEW YORK.

MACHINE FOR FCJRWI'IZEI'G SPIRAL TUBING.

v Specification of Letters latent.

Patented'Nov. 17., 1914.

` Application led October 1, 1910. Serial No. 584,925.,y

To all 'whom 'it may concern:

Be it known that I, ADNAH MoMUnTmE, of New York, N. Y., have inventedcertain Improvements in Machines for Forming Spi forming spiral tubing,and is of particularA utility when employed in apparatus for manufactureof the helically coiled metal strip used as a rotective armor sheath forinsulated electrical conductors, although I contemplate the use of myimprovements in any field to which they are adaptedby their nature. f

An important Object of my invention 1s to provide apparatusior, a moregradualhelical deformation of the somewhat resilient metal strip ofwhich such sheaths a e usually formed, than has been custo ary incoiling such articles heretofore, and accordingly I contemplate thetreatmentbf the strip by forming the convoliitions primarily of greaterdiameter than that of the finished tube, and thereafter reducingvgradually but steadily, withoutlundue prolongation ofthe treatment, thediameter of the convolutions to the desired size. l

Another important object `of my invention is to accomplish in a unitaryoperation with the aforesaid helical shaping' of the tube, the lateraldeformation o f the'stri along the axis of the helix, which isordinarily accomplished by treatment of the l strip in @separate machinepreliminary to the ccilingoperatio'n, in order to impart to y .the stripthe lateral curvature which has` usually constituted the' preparationofthe strip for its helical formation. My invention utilizes a straightstrip instead of a laterally curved strip, in the helix coiling machine.

Armor strips vat the present time are of rsubstantial width andthickness -owing to the requirements of the tire underwriters andbuilding authoritiespand the exigencies of modern building, which makeit necesthat the armor shall. so far as possible `'be capable ofresisting puncture by nails Sary and other destructive agencies, andsuch a substantial armor strip is difficult to deform laterally,especially when the strip is" of a more or less acutely bent cross4section for purposes of causing interlockingof the convolutions intheir helical form, these difficulties militating strongly against aready Y reduction of the strip to final spiral form during the formationof the first convolution, as has been the practice heretofore in themanufacture of such armor sheaths.

Any suitable device may be adopted to carry my invention into effect,and as the preferred form of such device I may employ an apparatuscomprising rolls presenting working surfaces for en agement with `thestrip at an angle to the a "s ofthe helix of its formation, the angularrelation being secured as desired and found suitable in varioussituations, as for example, by using substantially straight rolls setatan angle to the axis of the helix, and farther away from said axis atthe initial point of convolution, or point of entrance of the strip,than at the region'of exit of the finished article.

The various features of my invention will be illustrated and describedfully in the accompanying drawings and specification and pointed out inclaims.

In the drawings Figure 1 is a view'in front elevation of the preferredform of apparatus for carrying my invention into effect, and inthe'construction of which my improvements have been embodied; Fig. 2 isa conventional section taken on the line azz-m of Fig. l; and Fig. 3 isa fragmentary View similar to Fig. 2, showing in vertical longitudinalsection a modified form of roll 'for usein my improved machine; WhileFig. ,4 is. a sectional view of a suitable strip for treatment. Y l

In the embodiment ofmy invention selected for illustration anddescription to permit a ready and complete understanding ofthe preferredmanner -in Awhich my invention may be carried into effect, the partdesignated by the reference numeral 201 is av device for deforming'thestrip 205 constituting the stock under treatment to form a .flexiblemetallic armor tube in the instance illusicc;

trated, andthe device itself may be of any oint of entry and 'at asuit-able distance rom the' helical axis, this distance being greaterthar the radius of the completed sheath, iandtin* the instanceillustratedthi's p urpOseis-served,

as desired and found suitable to the exigencies of the Work on hand;thus I have shown four rolls bearing the reference numerals 201, 202,203 and204 respectively, each with an arbor 207 having its axis inclinedto the common central axis of the machine, along which the helix is tobe formed, and the face of the standard 208 is preferably constructedwith its respective portions as right angles to the axes of the rolls..I prefer also to provide the apparatus with means to drive these rollspositively, for which purpose I have shown the arbors 207 as extendedbeyond the bearing standard 209, and provided respectively with pinions213, keyedl at 214 to their arbors respectively, and meshing with a gear215 secured by key 216 upon av hollow shaft 217, also journaled in theAframe kupright 209, this shaft being provided withsui'table means suchas the gear 21S keyed theretoiat 219 to permittheshaft to be driven froma suitable source of power (not shown).

I have shown a bearing standard 221 bolted at 212 to the base 210 andaffording a bearing for the hollow shaft 217, the face of the standardbein preferably dished in order that this stan ard may be utilized as athrust bearing for the arbors 207.

lVhen it is desired to form the sheath 225 in place upon an insulatedconductor such as that shown at 226, the latter maybe introduced to thesheath through the axial bore of the shaft 217, and the insulatedconductor will preferably, but not necessarily, be rotated with theshaft 217 and sheath 225 during the formntionof the latter, but inasmuchas such insulated conductors are ordinarily of non-circular contour asillustrated, the sheath need not fit thereupon with greater closenessthan will constitute an easy slip t, the conductor performing nospecilic function in the formation of the convolutions of the sheath, aswill be readily understood by reference to'Fig. 2 of the drawings.

The relatively vlarge distance between the rolls at their ends adjacentto the region of entrance of the strip 205, and the correspondinglylegge diameter of the first convolution, vren ers its lateraldeformation easy, so that I the helical lay is imparted with leastresistalice onthe part of the strip owing to the elimination qf much `ofthe radial resistance to bending, and when the first convolution hasbeen made the subsequent reduction of the diameter of the helix 1saccomplished ,by successive circumferential bending strains and byincreasing lateral deformation.

In the preferred. -form of machine illus- .trated in Fig. 2, the hollowshaft terminates outside of' the region of operation of the rolls, but Imay provide a mandrel of suitable length, and of any suitableconstruction and arrangement, as for example, by providingV the hollowshaft 217 with an .integral extension 277, whichmay be formed tapered asillustrated by the dotted lines in Fig. 2.

In Fig. 3 I have shown a modified form of roll comprising a sleeve 301secured by a key 306 upon an arbor 307.

I have shown in Fig. 4 in cross section one convenient form of strip 205for use 1n the manufacture of helical sheaths, but I do of limit myselfto any particular cross section of strip for this purpose.

In the operation of my improved apparatus, the rolls 201, 202,' 203, 201being rotated by actuation of gears 213 through the medium of gear 215upon the hollow shaft 217, which is driven by' the gear 218 actuated inturn from a suitable source of ower (not shown), 'act upon the strip 205ed thereto in the usual manner from the side, and the strip beingengaged with the initial convolution, say of the roll 202 in the lowerAleft handv osition illustrated in Fig. 2, and therea r en aged with'aroove upon the roll 203 which is setsli htigy in advance of the positionof the initia groove in roll 202, and similarly. when the strip 205lpasses to grooves on the rolls 201 and 201 successively, therespectively advanced position of these grooves develops helicaldeformation of the i strip, and feedsit forward into engagement withsuccessive grooves, which operate in turn to feed forward the helicaltube thus formed, the rolls 'serving by their angular disposition toform said helix in progressively decreasing'convolutions.

I do not claim herein specifically certain features of constructionwhichform the subject matter of the claims in my cio-pending applicationsSerial Nos. 581,923; 584,924; 584,926 and 584,927.

Having illustrated and described my invention thus fully, and suitablemeans b which it may be carried into effect, I wis it to be understoodthat I do not limit myself to the specific construction and materialsshown and described by way of example, nor do I limit myself in generalotherwise than as set forth in the claims 'read in connection with thisspecification.

What I claim as new and desire to secure by Letters Patent of thc UnitedStates of America is 1. Ceiling apparatus; comprising aset off rollsrotatable respectively about axes'ang;

constructed and arranged. 4to deform a strip helically, and approachingsaid axis in the direction of formation of said helix to form said helixin progressively decreasing com volutions.

2.1Coiling apparatus; comprising a set of rolls rotatable res ectivelyabout axes angularly disposed re atively to a common central axis, saidrolls havin forming-surfaces constructed and arrange to deform a striphelically, and approaching said axis in the direction cof formation of.said helix to form said helix in progressively* decreasingconvolutions; and a hollow shaft coni'iected with and to actuate saidrolls, and through which an insulated conductor may be led into thesheath constituted by said helix.

3. Coiling apparatus; vcomprung a setvof rolls' rotatable re activelyabout axes angularly disposed re atively to a common wie tral axis, saidrolls having forming-surfaces constructed and arranged to helically, andapproaching said axis in the direction of formation of said helix toform ysaid helix in 1progressively decreasing convoluti'ons; and ahollow shaft connected with fand to actuate said rolls,

and through which an insulated conductor may be led into the sheathconstituted by said helix, having a tapered orepart to serve as amandrel.

Signed at'New 'York in the county and State of New Yorkthis 26th day ofSeptember, 1910. 1

ADNAH MCMUR'IQRIE. Witnesses:

WM. H'. McCoRMrcx, ALEXANDER C; PROUDFIT.'

deiorm va strip said shaft

